1. Field of the Invention
The present invention generally relates to a control apparatus controlling rotation of a rotator.
2. Description of Related Art
A controller performing motion control uses a target value (position, speed, torque and the like) of an instruction in a user program to perform, at regular periods, output of an instruction position of a control object such as a motor and information obtaining from the control object required for implementing required actions. The controller, as disclosed in patent document 1, converts an instruction movement amount of the rotator to a unit of a pulse quantity processed by a servo driver.
For example, when the rotator is driven in a system which uses the motor to rotate the rotator such as a table, during manufacturing of the user program, an instruction position indicating a rotator position is set by using an angle as a unit. Correspondingly, a driver of the motor processes an instruction value by using a pulse as a unit. Therefore, the unit of the instruction position needs to be converted from an angle to a pulse quantity. For example, when the motor rotates for a turn from 0° to 360° and returns to 0°, in a coordinate system repeatedly rotating from 0°, a turn (360°) rotated by the motor is converted into a prescribed pulse quantity.